High Pressure Fittings

High-pressure Fittings

Developed through more than 95 years of experience in the pipeline industry, high-pressure fittings from TDW are furnished with patented features that can help operators safely and efficiently repair and maintain high-pressure lines without shutdown or interruption of service.  

All fittings are engineered to work seamlessly with TDW tapping and isolation equipment, including the STOPPLE® plugging machines and STOPPLE Train isolation systems, SHORTSTOPP® plugging machines, and TDW tapping machines.  

STOPPLE Plus fittings , for example, have no side openings in the flange, which reduces potential leak paths and significantly lowers risk when conducting line isolations. In addition, offerings like THREAD-O-RING® fittings provide value for purge and equalization operations, as they can easily accept corrosion test coupons, gauge adapters, instrument probes, and thermometer wells.

Whether for an isolation, bypass, purge and equalization, or blowdown, TDW can provide a high-pressure fitting that helps get the job done quickly, efficiently, and without incident.

Best used for: isolation operations on high-pressure transmission lines.

Key features:


  • What is the difference between the STOPPLE and the STOPPLE Plus fitting? STOPPLE Plus fittings are an alternative to the STOPPLE fittings. STOPPLE Plus fittings have no side openings on the flange, which helps eliminate potential leakage through the completion plug.
  • What ASME standards do STOPPLE and STOPPLE Plus fittings meet? Both the STOPPLE and STOPPLE Plus fittings are designed to meet ASME B31.3, B31.4, and B31.8 requirements.

Need help selecting the right fitting for your project? Click to enlarge the chart below.

TDW High-Pressure Pipeline Fitting Chart

Spherical 3 Way Tee

Spherical 3-WAY Tees

TDW Spherical 3-WAY™ tees are designed for use with SHORTSTOPP® plugging machines. The tees feature a low-profile design and are available in a variety of sizes, from 2 inches through 12 inches. Sizes 4-inch and above are equipped with a reusable bolt-on flange adapter to accommodate TDW SHORTSTOPP valves and SHORTCUTT® valves.

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Stopple Fittings

STOPPLE® Fittings

High-pressure STOPPLE fittings are designed for use with TDW STOPPLE plugging machines.

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Stopple Plus

STOPPLE® Plus Fittings

TDW STOPPLE® Plus fittings are full-branch split tees that can be used as an alternative to conventional STOPPLE fittings in a variety of hot tapping and plugging operations.

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Tapping Fittings

Tapping Fittings

TDW offers a comprehensive line of full-branch and reduced-branch split tee tapping fittings. They are available in a range of sizes, from 2 inches through 30 inches, to meet the specific requirements of various pipeline branching operations.

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Tread o Ring Fittings


TDW THREAD-O-RING™ fittings can be used as purge and/or equalization fittings in a variety of hot tapping and plugging applications. They are available in two sizes, 2-inch and 3-inch, and are mainly used with the T-101 drilling machine. They can also be used with the 360 tapping machine.

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